The Tangled Angles Game is a great way to get kids to develop an understanding of the different types of angles and to distinguish between acute, obtuse, right, straight, and reflex angles. Sometimes kids have a hard time understanding why a straight angle is even an angle, but the use of the geoboard makes that concept much clearer. You'll need a fairly large geoboard to ensure that you can follow the instructions that state not to let the arms of the angles cross over each other and not to reuse pegs. If the available geoboards are too small you may want to suspend at least one of those rules to ensure the students will have time and space to try every different type of angle. You might also ask students to not extend the sides of their angles more than three pegs in length to ensure that there will be plenty of space to create other angles.
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